Machine for punching out blanks of circular or regular polygonal shape from plates of sheet metal or the like.



PATENTED AUG. 29, 1905.

. G. P. HOPFMANN. I MACHINE FOR PUNGHING OUT BLANKS 0E CIRCULAR 0RREGULAR POLYGONAL'SHAPE FROM PLATES 0F SHEET METAL OR THE LIKE.

APPLICATION FILED DBO. 28,1904.

UNITED STATES PATENT OFFICE.

GOTTFRIED PHILIPP HOFFMANN, OF THUN, SWVITZERLAND.

MACHINE FOR PUNCHING OUT BLANKS F CIRCULAR 0R REGULAR POLYGONAL SHAPEFROM PLATES 0F SHEET METAL OR THE LIKE.

Specification of Letters Patent.

Patented Aug. 29, 1905.

Application filed December 28,1904. Serial No. 238,569.

To all whom, it may concern-.-

Be it known that I, Go'r'rrRIED PHILIP]? HOFFMANN, a citizen ofSwitzerland, reslding 1 at Thun, Canton of Berne, Switzerland, haveinvented certain new and useful Improvements in Machines for PunchingOut Blanks of Circular or Regular Polygonal Shape from Plates of SheetMetal or the Like, of which the following is a specification.

This invention relates to machines for punching out blanks of circularor regular polygonal shape from plates of sheet metal or the like. Inorder to properly position the plates between the puncher and the die,stops are used which usually are arranged at a fixed angle of ninetydegrees with relation to each other, so that the centers of adjacentblanks to be cut out form when connected by lines rectangles.

The present invention has for its principal object to out the blanks insuch a manner that each row of blanks will be oifset with relation tothe preceding row, so that the centers of adjacent blanks form whenconnected by lines equilateral triangles, whereby a considerable savingin material is obtained. To this end, two stops for positioning theplates, from which the blanks are to be cut out, between the puncher andthe die are provided, one of which stops is adapted to be rotated aroundthe axis of the puncher and to be secured in various angles withrelation to the other stop, which only is adapted to be adjusted in aradial direction with respect to the axis of the puncher, whereas theother stop can be adjusted circumferentially as well as radially.

In the accompanying drawings, Figure 1 is a plan view of my improveddevice, and Fig. 2 a front elevation, partly in section, on a a planethrough the line A B of Fig. 1.. Fig. 3 is a side View viewed from theleft of Fig. 1, whereas Figs. 4 and 5 represent plates, showing thevarious forms of the blanks out out and showing how each row of blanksto be out out is offset with respect to the preceding row.

Similar reference characters are used to designate similar parts in allthe figures.

represents the puncher, adapted to be moved up and down away from andtoward the support 6, which is arranged within the socket 0 andsupported by springs .9, held in suitable apertures in the said socketc. The latter is secured in a base d, provided with an upward annular[extension 6, projecting ring f, having fastened to it by means ofscrews l the stop g. The screws Z pass through slots it of a lug it madeintegral with the stop 9, so that the latter can be adjusted to vary itsdistance from the axis of the puncher b at will. The ring f is furtherprovided with a handle 1;, having pivoted to it' the locking-lever 71:,one arm of which is normally raised by a spring 71 so that a locking-pinm is held in engagement with an aperture 7', provided in the base (Z,thereby securing the handle 6 and the ring f in their positions. Thereare three apertures r, 1", and r in the base-plate (Z and by forcingdown the free end of the locking-lever against the pressure of thespring a the locking-pin m at the other end of the lever is lifted outof one of the apertures, and then by moving the handle 11 in one or theother direction the ring f and therewith the stop g are also moved untilthe locking pin on is opposite another aperture, when by releasing thepressure "on the free end of the lever in the pin 77?. will be forced bythe spring a into the said aperture, thereby locking the ring f and thestop g in their positions.

To prevent the ring from leaving the extension 6, a ring 0 is fastenedby screws or similar means to the extension 0, as shown in Fig. 2,whereby the ring f is securely held against any movement in axialdirection.

A second stop 79 is secured to the base-plate d by means of screws 9,passing through slots p in the base of the stop, whereby the stop can beadjusted radially with respect to the axis of the puncher (0, whereasthe stop 19 cannot be adjusted in a circumferential direction.

In order to cut out from a plate circular blanks, as shown in Fig. 4.,the puncher a and the die 0 must be of course of circular form. Afterthe handle a has been moved into the position shown in Fig. 1 in fulllines, which position is designated by I, the movable stop 9 will formwith the fixed stop 9 an angle of ninety degrees. Both stops are thenradially adj usted so that the distance between their engaging faces andthe axis of ,the puncher a is like half the diameter of a blank to becut out. The plate P (shown in Fig. 4) is then placed with its left-handupper corner on the support 6, so that the stops and g are in contactwith the edge of the plate at the points 1 1, Fig. 4, when the firstblank is cut out. The plate]? is then moved into a position where thestops 1) and 9 come in contact with the plate at 2 2, after whichanother blank is cut out. Each time after a blank has been cut out theplate is moved until the stops come in contact with the platesuccessively at 3 3, 44, &c. After the first row of blanks has been thuscut out the handle o' is moved into the position designated in Fig. 1 byII, whereby the stop 9 is moved from its former position over an arc ofthirty degrees. The plate P, Fig.

( 4, is now again placed first with its' upper left-hand corner on thesupport 6, so that the stop g comes in contact with the plate at 7,whereas the left-hand side of the plate is placed in the center line C Dof the support 6. In this position of the plate only half a blank isfirst cut out, after which the plate is moved until the stops p g are incontact with the plate at 8 8, Fig. 4. A full blank is now out out andthe plate is then moved on as above successively into the position wherethe stops 1) gcome in contact with the plate at 9 9, 10 10, 11 11, 1212,and after each adjustment of the plate a blank is cutout. After the nextto the last blank in the second row has been cut out the handle 6 on thering f again is moved, this time into the position shown in dotted linesand designated by III in Fig. 1, whereby the movable stop g is movedtoward the stop 2) the distance between the two stops, thus including anarc of sixty degrees. The plate P is now so positioned on the supportthat the stops 1) and g come in'contaot with this plate at 13 13, Fig.4. In order to punch out the blanks in the third row, the movable stop gremains in the position last referred to, whereas for cutting out thefourth row the stop g is again returned to the position which the stopoccupied to cut out the second row.

As seen from Fig. 4 the centers ofthree adjacent blanks to be cutoutform the corners of an equilateral triangle and the stop g, asdescribed, is alternately positioned, so that its distance from thefixed stop 9 includes first an arc of 90, then of 90 4-80 120 and thenof 90-30:60.

Of course other than circular blanks can be cut out in the same manneror following the same principles. Fig. 5, for instance, shows a portionof a plate P from which blanks in the form of regular hexagons are cutout, and also in this case the centers of three adjacent hexagons formthe corners of an equilateral triangle and the stop g is also for thisoperation alternately so adjusted, so that its distance from the fixedstop 2 includes first an arc of 90 then of 9O +3O :120 and then 2. In apunching apparatus the combination with a movable puncher and a die, oftwo stops for determining the position of the work, one stop having afixed position, and a movable ring carrying the other stop and adaptedto be rotated around the axis of the puncher, and a handle attached tosaid ring, whereby the ring and the stop carried by it can be movedtoward and away from a fixed stop.

3. In a punching-machine the combination with a movable puncher and adie, of two stops, one of saidstops being attached to a movable ringadapted to be rotated around the axis of the puncher and held againstaxial movement, a handle secured to said ring and a locking-leverpivoted to said handle, a locking-pin at one end of said lever and aspring pressing against the other end thereof to force said pin into oneof a series of apertures arranged in the base-plate of the machine tohold the ring in its various positions.

4. In a punching-machine the combination of a movable puncher and a diecooperating therewith, of two stops, one of said stops being adapted tobe moved away from and toward the other stop, both stops being radiallyadjustable with respect to the axis of the puncher.

In testimony whereof I aflix my signature in presence of two Witnesses.

GO'ITFRIED PHILIIP HOFFMANN.

Witnesses:

A. LInBERKNEoH'r, O. H. CLoTTER.

